There are 2 RNG involve at the very start of the battle: (1) if Zwei uses WA; or (2) if Zwei didn't fall asleep from your Hisham's Blast Bomb (65%). If any of this happens, just redo.

Q: Why Blast Bomb and not Bagua Sunlight at early? A: It doesn't have cast time so it saves my Kudan from getting hit. Q: Why Hisham and not any other Desert unit with Sleep (like Aswald) who can equip Balt's memento "Burning Desert Vow"? A: Hisham starts with full jewel and VA Sandstorm Tailwind cost 60 jewel. Also, Hisham has supportive ability from his J+ that provides jewel regen.